{"id":"CVE-2026-19600","state":"PUBLISHED","title":"Mattermost logs plaintext authentication tokens in debug-level server logs on failed auth attempts","description":"Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763","publishedAt":"2026-10-16T07:07:17.899Z","updatedAt":"2026-10-16T12:02:51.761Z","severity":{"score":4.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N","source":"Mattermost"},"assigner":"Mattermost","products":["Mattermost Mattermost"],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"11.9.0","status":"affected","lessThanOrEqual":"11.9.1","versionType":"semver"},{"version":"11.8.0","status":"affected","lessThanOrEqual":"11.8.5","versionType":"semver"},{"version":"11.7.0","status":"affected","lessThanOrEqual":"11.7.10","versionType":"semver"},{"version":"11.10.0","status":"affected","lessThanOrEqual":"11.10.1","versionType":"semver"},{"version":"11.11.0","status":"unaffected"},{"version":"11.9.2","status":"unaffected"},{"version":"11.8.6","status":"unaffected"},{"version":"11.7.11","status":"unaffected"},{"version":"11.10.2","status":"unaffected"}]}],"references":["https://mattermost.com/security-updates"],"weaknesses":["CWE-532"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/19xxx/CVE-2026-19600.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-19600","state":"PUBLISHED","datePublished":"2026-10-16T07:07:17.899Z","dateUpdated":"2026-10-16T12:02:51.761Z","assignerShortName":"Mattermost","assignerOrgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateReserved":"2026-08-12T07:12:44.545Z"},"containers":{"cna":{"title":"Mattermost logs plaintext authentication tokens in debug-level server logs on failed auth attempts","descriptions":[{"lang":"en","value":"Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763"}],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"11.9.0","status":"affected","lessThanOrEqual":"11.9.1","versionType":"semver"},{"version":"11.8.0","status":"affected","lessThanOrEqual":"11.8.5","versionType":"semver"},{"version":"11.7.0","status":"affected","lessThanOrEqual":"11.7.10","versionType":"semver"},{"version":"11.10.0","status":"affected","lessThanOrEqual":"11.10.1","versionType":"semver"},{"version":"11.11.0","status":"unaffected"},{"version":"11.9.2","status":"unaffected"},{"version":"11.8.6","status":"unaffected"},{"version":"11.7.11","status":"unaffected"},{"version":"11.10.2","status":"unaffected"}]}],"references":[{"url":"https://mattermost.com/security-updates","name":"MMSA-2026-00763","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"NONE","version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N","baseSeverity":"MEDIUM","baseScore":4.5},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-532","lang":"en","type":"CWE","description":"CWE-532: Insertion of Sensitive Information into Log Files"}]}],"providerMetadata":{"shortName":"Mattermost","orgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateUpdated":"2026-10-16T07:07:17.899Z"},"credits":[{"lang":"en","type":"finder","value":"CERT PL"}],"solutions":[{"value":"Update Mattermost to versions 11.11.0, 11.9.2, 11.8.6, 11.7.11, 11.10.2 or higher.","lang":"en"}],"source":{"advisory":"MMSA-2026-00763","defect":["https://mattermost.atlassian.net/browse/MM-70207"],"discovery":"EXTERNAL"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-16T12:02:37.754353Z","id":"CVE-2026-19600","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T12:02:51.761Z"}}]}}}